Aqueous mixture and silicone oil in water emulsion containing siloxane wetting agents



United States Patent 6 Claims. (Cl. 252312) ABSTRACT OF THE DISCLOSURE This invention relates to the use of a small class of low molecular weight, hydrolytically stable siloxane-oxyalkylene copolymers as wetting agents in aqueous solutions and in silicone oil in water emulsions. The ability of these specific copolymers to promote wetting is far superior to that of other copolymers in the same general class.

This application is a division of application Ser. No. 376,549, filed June 19, 1964, said application is now US. Patent 3,299,112, and the latter application is a continuation-in-part of application Ser. No. 823,290, filed June 29, 1959, now abandoned.

This invention relates to organosilicon compounds and, in particular, to alkoxypoly(ethyleneoxy)siloxanes that are particularly useful as wetting agents in aqueous systerns.

This invention provides novel siloxanes containing only (a) an alkoxypoly(ethyleneoxy)siloxane group and (b) from 1 to 4 methyland/ or ethyl-siloxane groups. More specifically, this invention relates to siloxanes containing only (a) one group having the formula:

I O SiCmHz (OCzH (O C 11 p0 R and (b) from 1 to 4 groups having the formula:

RbSiOi wherein:

(1) a has a value from 0 to 2 inclusive;

(2) b has a value from 2 to 3 inclusive;

(3) R is a methyl or an ethyl group;

(4) R is an alkyl group containing from 1 to 4 carbon atoms inclusive (i.e., a methyl, ethyl, propyl or butyl p);

(5) m has a value from 2 to 4 inclusive;

(6) n has an average value from about 4 to 17 inclusive;

(7) p has an average value from 0 to 5 inclusive;

(8) the ratio of n to p is at least 2 to 1;

(9) n+p has a value from about 4 to 17 inclusive (preferably from 4 to 12 inclusive); and

the alkoxypoly(ethyleneoxy) group is attached to the silicon atom of formula (A) through at least two carbon atoms of the C H group.

These siloxanes are often mixtures whose average composition can be represented by formulae (A) and (B) above, wherein n and p can have fractional values.

Three preferred classes of the siloxanes of this invention are those having the formulae:

I (Me SiO) zbiCmHzm (0 0 11 0 R wherein q has an average value from about 4 to 12 inclusive, Me represents a methyl group and the remaining symbols have the meanings defined above.

Specific siloxanes of this invention are illustrated by those having the following formulae:

O l (Me2Si0) (MeSiO H (O CzllmOMe) (cytlic tetramor) The siloxanes of this invention are readily prepared by an addition reaction between a hydrosiloxane (i.e. a siloxane containing silicon-bonded hydrogen) and an alkenyl ether (eg, a vinyl, allyl, or methallyl ether) of an alkoxy and hydroxy end-blocked poly(ethylene-oxide). The reaction conditions employed in addition reactions of this type are well known in the art and in general involve heating the reactants (e.g., at a temperature of from about C. to 110 C.) in the presence of a platinum catalyst (e.g., chloroplatinic acid) and a solvent (e.g., toluene).

The siloxanes of this invention are remarkably efiective in promoting the wetting of various surfaces, particularly surfaces that are difficult to wet, by aqueous emulsions and solutions. This property makes the siloxanes admirably suited as additives for aqueous paints, adhesives, printing inks, dyeing baths and emulsions which must thoroughly wet surfaces in order to function properly. The siloxane is desirably added to the water in such systems in an amount from 0.001 to 2 parts by weight per parts by weight of the water. The effectiveness of the siloxanes of this invention as wetting agents is far superior to that of other siloxanes of similar structure as demonstrated in the examples presented below. In particular, the siloxanes of this invention are useful as wetting agents in silicone oil-in-water emulsions wherein the silicone oil is a diorganopolysiloxane having the formula:

wherein R is a hydrocarbyl group and x has a value from 10 to 1,000. Illustrative of the monovalent hydrocarbon (hydrocarbyl) groups that are represented by the roups (for example, the cyclohexyl group). Preferably, re silicone oil is a dimethylpolysiloxane having the foriula Me SiO Me SiO SiMe here at has a value from S to 400. In such emulsions, the licone oil is preferably present in an amount from 1.0 parts by weight per 100 parts by weight of water in 1e emulsion. The siloxane of this invention is preferably resent in the emulsion in an amount from 0.1 to 0.5 arts by weight per part by weight of the water in the mulsion. In such emulsions, the siloxanes of this invenon function as an emulsifying agent as well as wetting gents. Such emulsions can also contain conventional oranic emulsifying agents such as those described below 1 the examples. Such emulsions can be prepared by conentional means. These emulsions are useful for treating lncured rubber (e.g. neoprene) articles prior to the lolding thereof to facilitate the subsequent release of the ured molded rubber product from the mold. Alternately he molds themselves can be pre-treated with such emulions. In addition, the emulsions are useful in treating sphalt floor tiles prior to packing and shipment to minimize adhesion of the tiles to each other.

In addition, the siloxanes of this invention can be added 0 any of a variety of other aqueous systems to improve he wetting of various surfaces by such systems. By way )f illustration, the siloxanes can be added to aqueous lfllIltS, aqueous adhesive compositions, aqueous printing n-ks, aqueous dyeing baths and aqueous mold release com- )ositions to improve the wetting of such materials as poly- :thylene, steel, aluminum, wood, fibrous materials or Feflon.

The following examples illustrate the present invention.

EXAMPLE 1 A siloxane of this invention was produced by forming a. mixture of 60.0 grams of toluene and 39.0 grams (0.1 1101) of CH =CHCH (OC H OMe in a 300 milliliter lask connected to a distillation column fitted with a distillation head, a receiver and a Dry Ice trap. The flask is swept with a nitrogen purge. A small amount of water present in the mixture was removed by azeotropic distillation. Then 24.4 grams (0.110 mol) of Me SiO (MeSiHO SiMe was added to the flask. Two drops (6X 10- mol) of chlo- ."oplatinic acid dissolved in ethanol were then added to the flask and the contents of the flask were heated 175 C. for 17 hours. The reaction product was cooled to 25 C. and activated charcoal was added. The mixture of the activated charcoal and the reaction product was filtered through a filter medium to remove the activated charcoal and the platinum (adsorbed on the charcoal). The toluene was removed from the reaction product by distillation and volatile materials were removed from the reaction product by heating at 150 C. at one millimeter of mercury pressure for one hour. The final product was a siloxane of this invention having the formula:

This siloxane is referred to hereinafter as Siloxane I (abbreviated Sil I).

The following examples illustrate the use of siloxanes of this invention as wetting agents.

In the examples appearing below, the ability of emulsions and aqueous solutions to wet various surfaces was measured by the following procedure: By means of a syringe exactly 0.02 milliliters of emulsion (or solution) was deposited on the substrate. After three minutes the average diameter of the drop was measured by means of a vernier caliper. Tests were run in triplicate. Percent increase in drop diameter was calculated as follows:

Percent increase in drop diameter= A X 100 A=diarneter of drop of distilled water applied to the surface in the same manner.

B=diameter of drop of test emulsion (or solution) after 3 minutes.

In the examples appearing below, the siloxanes of this invention are compared to various commercially available wetting agents and emulsifying agents. The commercially available wetting agents and emulsifying agents are as follows:

Trade name: Composition Tergitol Aqueous solution containing Anionic 7 25 weight percent sodium heptadecylsulfate (balance water).

Tergitol TMN Aqueous solution containing weight percent polyoxyethylated trimethylnononol (balance water).

Alconox Alkylarylsulfonate.

Aerosol AY Sodium diamylsulfosuccinate.

DOWfaX In the examples, the trade name or the composition or both are used to identify these materials.

In certain of the examples appearing below, the following abbreviated symbols are used to represent various groups that compose siloxanes of this invention and to represent starting siloxanes from which they are produced. In addition these symbols are used to represent other siloxanes whose wetting properties are described for comparison purposes.

In the following examples, the dimethylsiloxane oils used had the formula Me SiO(Me SiO) SiMe EXAMPLE II The following emulsions (formulations) were formed by mixing the indicated ingredients.

Weight Percent Formulation Polyoxy- Polyoxy- Dimethyl- Water Sil. I ethylated ethylated siloxane oil Fatty N onyl- Alcohols l phenol B {Azgrnixture of 1.75 wt. percent Bi'ij 30 and 1.75 wt. percent Sergitol NP 35.

Two portions of Emulsion A was diluted with water to 3.5 and 1.0 wt.-percent dimethylsiloxane oil respectively, the diluted emulsions being designated A-3.5 and A-l, respectively. Similarly, Emulsion B was diluted with water to 3.5 and 1.4 wt.-percent dimethylsiloxane oil respectively, the diluted emulsions being designated B3.5 and B-l. Wetting by these diluted emulsions was measured on clean aluminum and cold-rolled steel surfaces:

Percent Increase in Drop Diameter Steel Aluminum The results demonstrate the greater wetting power of an emulsion containing Siloxane I (prepared as described in Example I above), as the wetting agent as well as the primary emulsifier compared with an emulsion containing only an organic emulsifier.

EXAMPLE III The following emulsions were formed by mixing the indicated ingredients.

Dirnethyl- Polyoxy- Formulation Siloxane oil Sil. I H O ethylatecl Fatty Alcohol 1 1 Brij 35.

Both of these emulsions were diluted with water to 1 wt. percent dimethylsiloxane oil. Diluted A and B were called A1 and B-1, respectively. To an aliquot of B1 was added 0.1 wt. percent Siloxane I. This modified emulsion was designated V-2. The results of wetting of uncured freshly-sheeted neoprene with these emulsions were:

Percent increase in drop diameter A-1 87 B-l 32 B-2 80 These results demonstrate the better wetting resulting from using Siloxane I as the only emulsifier (A-l) or addition of Siloxane I to an emulsion containing an organic emulsifier (B-2).

EXAMPLE IV The following emulsions were formed by mixing the indicated ingredients.

Formulation A: Weight percent Dimethylsiloxane oil 35.0

3 5 15C3H5- SiMeO] SiMe 3.5 Water 61.5 Formulation B Weight percent Dimethylsiloxane oil 35.0

Polyoxyethylated nonylphenols (a mixture of 2.1 Wt. percent Renex 678 and 1.4 wt. percent Renex 690) 3.5 Water 61.5

Also contains 0.3 part by Weight of a preservative for controlling bacteria.

Formulation C Weight percent Dimethylsiloxane oil 35.0 Me SiO[MeO(C H O) C H SiMeO]SiMe 2.6 Polyoxyethylated nonylphenol (Tergitol NP35) 0.9 Water 61.5

'-Als0 contains 0.3 part by weight of a preservative for controlling bacteria.

Emulsions A, B, and C were diluted with water to 3.5% dimethylsiloxane oil. These diluted emulsions were called A-l, B-1, and C-1, respectively. To aliquots of each diluted emulsion was added 0.2 wt. percent Siloxane I,

these emulsions being then designated A-2, B-2, and C-2. Wetting tests were run on uncured neoprene sheet and also polyethylene sheet.

Percent Increase in Drop Diameter Sample Neoprene Polyethylene For all three emulsions, addition of Siloxane I improved the spreading, or wetting, on both neoprene and polyethylene. The eifect was demonstrated where the initial emulsifiers were a siloxane-oxyalkylene copolymer (not of the class used in this invention) only (A), an organic wetting agent only (B) and combination of an organic wetting agent with Siloxane I (C).

EXAMPLE V The following emulsions were formed by mixing the indicated ingredients.

Formulations: Weight percent Dimethylsiloxane oil 35.0

Water 61.5

Polyoxyethylated fatty alcohol (a mixture of 1.75 Wt. percent Brij 30 and 1.75 wt. percent Brij 35) 3.5

Dimethylsiloxane oil 35.0

Water 61.5

Polyoxyethylated fatty acid esters (a mixture of 2.34 wt. percent Tween 80 and 0.29 wt. percent Atmos 300) 2.63

Each emulsion was diluted 20/1, i.e., 20 parts H O/l part above concentrates. To separate portions of diluted Formulation A was added:

Weight percent Siloxane I 1.5 Tergitol Anionic 7 (25% aqueous sodium heptadecyl sulfate solution) 1.5 Tergitol TMN polyoxyethylated trimethyl nonanol aqueous solution) 1.5

Siloxane I 0.6 Tergitol Anionic 7 1.2 Tergitol TMN 1.2

Drops of each of these three emulsions, and also drops of a control, were applied to a varnished wooden panel. As in formulation A, Siloxane I have excellent wetting, i.e., greater than 300% increase in drop diameter. The other emulsions gave poor wetting.

EXAMPLE VI This example illustrates the superior wetting of steel, glass, polyethylene and Teflon by aqueous solutions containing small amounts of Siloxane I. For comparison 75 purposes, the wetting of such surfaces by aqueous soluns containing commercially available wetting agents id a siloxane not of this invention (Siloxane A) was also TAB LE III easured. 5110113116 A h s t formula- 1.0 wt. percent Percent Increase in Diameter of a Water Clone of fSiloxafiles Droplet (0.02 ml.) after 3 min. aVlD. OIIIIH a Me S1O(MeO(C H O) C H S1MeO) S1Mc %.ni xoMe (1 10 Steel Glass Polyethylene The results of these wetting tests are shown in Table I :low. In the table, wets indicates that the droplet of 3 1e test solution increased in diameter over 300 percent. Wets Wets 228 he numerical values in the table indicate the percent ingg ease in diameter of the droplet of test solution applied a the surface.

TABLE I Percent Increase in Diameter of a Wt. Water Droplet (0.02 ml.) after 3 min. Surfactant Percent Cone.

Steel Glass Polyeth- Teflon ylene lloxane I 1. 0 Wets Wets Wets 151 D 0. 1 Wets Wets Wets 118 0. 01 Watts 145 170 67 1.0 194 61 109 56 0. 1 47 14 35 D0 0. 01 0 4. 5 12 13 .erosol AY+15% NazSOr 2 1. O 122 109 142 97 .erosol AY+15% NazS04 0.1 47 50 86 67 .erosol AY+15% NB2SO4- 0. 01 33 4 5 14 5.1 owiax 9N9 1. 0 126 52 91 44 lloxane A 1. 0 Wets 152 146 69 D0 0.1 Wets 126 69 1 WettingGood: 300% increase in droplet diameter (wets); fair: 100 to 300% increase 1 droplet diameter; poor: 100% increase in droplet diameter.

2 NazSO; added to decrease solubility of Aerosol AY.

EXAMPLE IX EXAMPLE VII In this test, a modification of the standard Draves Test vas used. The modification is described by L. Shapiro in American Dyestufi" Reporter, 39, 38 (1950). The test nvolves placing woven canvas tape on the surface of the 40 TABLE W est solution and measuring the time required for the tape P t I 1 D1 t I vo become totally immersed (sink) in the solution. In ggfg gfggf 2 fifff f g :ach test the solution consisted of water and the indicated Me(I\ 4 cag 0):giG l 1lCHzCHr Minutes amount of the wetting agent. For comparison purposes, the results obtained with a commercially available wetting Polyethylene Teflon tgent (Aerosol OT) are also shown in Table II. The Wets 118 results obtained with both wetting agents at 0.1 and 0.1 gets 156 Weight percent concentration are equivalent. The results i 2 obtained at 0.01 and 0.001 weight percent concentration Wets 97 4 show the superiority of Siloxane I.

EXAMPLE X TABLE 'II t This experiment demonstrates the superlor performance o'p sn n of the siloxanes of this invention as wetting agents in water as compared to other siloxanes.

Wt. Percent Cone. Sinking Wt. Percent Cone. Sinking TABLE V Time (sec.) Time (sec) 0 1 Wetting Percent Increase in Droplet Diameter 4 5 1 Wt. Percent Aqueous Solution of- 34 17 50 40 Glass Polyethylene Siloxfianfi; ogllliilsfinfieiitionz 1 a 1 4 7 e 225 W t EXAMPLE VIII Da[D'(C2H40)mM/] 2 268 33% S ga%;281g48)um%e 223 281 This etamplel lilllustratesghe importanlce of havijrzighabout fii'f'ghrfig gg lii il"1:11:11: 32 iiggts at east our et y ene 0x1 e units in si oxanes o t is ini 4 MDM o Y vention. As is shown in Table III, for a homologous MD'Mioigigigj% mmml g? Other Siloxanes: series 0fhS1}0XaIl6S 1fi 1 gdP X by tlhle agerage number MFWOIHOMMQ 4 of oXyet y ene units (re 1 ering o y y the average 70 [M;(C,H O) Me];O 57 74 value of the subscript x) poor Wetting 1s obtalned when 1% 9 109 116 [D (CaH4O)n 8137M. 111 51 the siloxane has fewer than about four oxyethylene. In M[D(C H O);Me]3- M 57 86 each run in Table III a mixture of siloxanes (1.0 wt. percent) having various numbers of oxyethylene units was 1 Symbols defined above after Example I. added to water to form the test solution. 2 Cyclic temmer' 9 EXAMPLE XI This experiment demonstrates the superior performance of a siloxane of this invention as wetting agents as compared to other siloxanes.

TABLE VI Wetting of Polyethylene, Percent Increase in Droplet Diameter 1 Wt. Percent Aqueous Solution of EXAMPLE XII The following table shows the superior wetting of polyethylene by various siloxanes of this invention produced by the above described addition reaction between hydrosiloxanes and allyl ethers of polyethylene oxides.

TABLE VII 1 Wt. Percent Aqueous Solution of Reaction Product of Equal Moles ol Wetting Percent Increase in Droplet Diameter Siloxane Ether MDDDM AMP G547 214 MDDDM- AMP G627 200 MDM AMP G398 Wets D D AMP G380 Wets MM" AMP G209 Wets Mfl". AMP G610. Wets AMPG" denotes the allyl ether of methoxy end-blocked polyethylene glycol (Le. CHfl=CHGH2(OCIH4)xOl\/Ie). The number following AMP G denotes the molecular weight of allyl ether.

What is claimed is:

1. A mixture consisting essentially of water and from 0.001 to 2 parts by weight per 100 parts by weight of the water of a siloxane composed of only (a) one group having the formula:

l osio...H,...(o c2114) n(003115) DO T (A) and (b) from 1 to 4 groups represented by the formula:

Rbsio 11b (9) n+p has a value from 4 to 17 inclusive; and (10) the alkoxypoly(ethyleneoxy) group is attached to the silicon atom of formula (A) through at least two carbon atoms of the C H group. 2. A mixture as defined in claim 1 wherein the siloxane has the formula:

0 wherein m has a value from 2. to 4 inclusive, q has an average value from about 4 to 12 inclusive, R is an alkyl group containing from 1 to 4 carbon atoms inclusive and the alkoxypoly(ethyleneoxy) group is attached to the adjacent silicon atom through at least two carbon atoms of the group represented by C H 3. A mixture as defined in claim 1 wherein the siloxane has the formula:

hide MezSiO S|iCmHam(O (EH4) qOR wherein m has a value from 2 to 4 inclusive, q has an average value from about 4 to 12 inclusive, R is an alkyl group containing from 1 to 4 carbon atoms inclusive and the alkoxypoly(ethyleneoxy) group is attached to the adjacent silicon atom through at least two carbon atoms of the group represented by C H 4. A mixture as defined in claim 1 wherein the siloxane is cyclic tetramer having the formula:

wherein in has a value from 2 to 4 inclusive, q has an average value from about 4 to 12 inclusive, R is an alkyl group containing from 1 to 4 carbon atoms inclusive and the alkoxypoly(ethyleneoxy) group is attached to the adjacent silicon atom through at least two carbon atoms of the group represented by C H 5. A silicone oil in water emulsion comprising (a) water, (b) from 0.1 to 5 parts by weight per parts by weight of water of a silicone oil having the formula:

wherein R" is a monovalent hydrocarbon group and x has a value from 10 to 1000 and (c) from 1.0 to 2 parts by weight per part by weight of the oil of a siloxane as defined in claim 1.

6. The emulsion of claim 5 wherein the silicone is a dimethylpolysiloxane oil having the formula:

Me SiO(Me SiO) SiMe where x has a value from 50 to 400.

References Cited UNITED STATES PATENTS 2,846,458 8/1958 Haluska 260448.2 3,299,112 1/1967 Bailey 260448.2

LEON D. ROSDOL, Primary Examiner.

RICHARD D. LOVERING, Examiner. 

1. A MIXTURE CONSISTING ESSENTIALLY OF WATER AND FROM 0.001 TO 2 PARTS BY WEIGHT PER 100 PARTS BY WEIGHT OF THE WATER OF A SILOXANE COMPOSED OF ONLY (A) ONE GROUP HAVING THE FORMULA:
 5. A SILICONE OIL IN WATER EMULSION COMPRISING (A) WATER, (B) FROM 0.1 TO 5 PARTS BY WEIGHT PER 100 PARTS BY WEIGHT OF WATER OF A SILICONE OIL HAVING THE FORMULA: 